COMPUTER SOFTWARE Computer software, or just software, is a collection of computer programs and related data that provides the instruction code for telling a computer hardware what to do and how to do it. Software refers to one or more computer programs and data held in the storage of the computer for some purposes. In other words, software is a set of programs, procedures, algorithms and its documentation concerned with the operation of a data processing system. Program software performs the function of the program it implements, either by directly providing instructions to the computer hardware or by serving as input to another piece of software.
Types of software
Software can be divided into twoparts:
System software and
Application
System software
System software provides the basic functions for computer usage and helps run the computer hardware and system. System software is responsible for managing a variety of independent hardware components, so that they can work together harmoniously. It includes a combination of the following:
An operating system (OS) is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system. A user cannot run an application program on the computer without an operating system, unless the application program is self booting.
Types of Operating system
Real-time: A real-time operating system is a multitasking operating system that aims at executing real-time applications. Real-time operating systems often use specialized scheduling algorithms so that they can achieve a deterministic nature of behavior. The main objective of real-time operating systems is their quick and predictable response to events. They have an event-driven or time-sharing design and often aspects of both. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.
Multi-user:A multi-user operating system allows multiple users to access a computer system concurrently. Time-sharing system can be classified as multi-user systems as they enable a multiple user access to a computer through the sharing of time. Single-user operating systems, as opposed to a multi-user operating system, are usable by a single user at a time. Being able to use multiple accounts on a Windows operating system does not make it a multi-user system. Rather, only the network administrator is the real user. But for a Unix-like operating system, it is possible for two users to login at a time and this capability of the OS makes it a multi-user operating system.
Multi-tasking vs. Single-tasking
When only a single program is allowed to run at a time, the system is grouped under a single-tasking system. However, when the operating system allows the execution of multiple tasks at one time, it is classified as a multi-tasking operating system. Multi-tasking can be of two types: pre-emptive or co-operative. In pre-emptive multitasking, the operating system slices the CPU time and dedicates one slot to each of the programs. Unix-like operating systems such as Solaris and Linux support pre-emptive multitasking, as does AmigaOS. Cooperative multitasking is achieved by relying on each process to give time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking. 32-bit versions, both Windows NT and Win9x, used pre-emptive multi-tasking. Mac OS prior to OS X used to support cooperative multitasking.
Distributed:A distributed operating system manages a group of independent computers and makes them appear to be a single computer. The development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine. When computers in a group work in cooperation, they make a distributed system.
Embedded:Embedded operating systems are designed to be used in embedded computer systems. They are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources. They are very compact and extremely efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems.
Examples of operating system
Windows, MS DOS, Linus, Macintosh, etc. Windows operating system is the most common OS and there are various versions from Windows 95 to Windows 7.
A Translators
A Translator is a computer program that translates one programming language instruction(s) into another programming language instruction(s) without the loss of original meaning.
Utility software is system software designed to help analyze, configure, optimize or maintain a computer. A single piece of utility software is usually called a utility or tool. Utility software usually focuses on how the computer infrastructure (including the computer hardware, operating system, application software and data storage) operates. Due to this focus, utilities are often rather technical and targeted at people with an advanced level of computer knowledge.
**Backup** utilities can make a copy of all information stored on a disk, and restore either the entire disk (e.g. in an event of disk failure) or selected files (e.g. in an event of accidental deletion).
**Data compression** utilities output a shorter stream or a smaller file when provided with a stream or file.
**Disk checkers** can scan the contents of a hard disk to find files or areas that are corrupted in some way, or were not correctly saved, and eliminate them for a more efficiently operating hard drive.
**Disk cleaners** can find files that are unnecessary to computer operation, or take up considerable amounts of space. Disk cleaner helps the user to decide what to delete when their hard disk is full.
**Disk compression** utilities can transparently compress/uncompress the contents of a disk, increasing the capacity of the disk.
**Disk defragmenters** can detect computer files whose contents are broken across several locations on the hard disk, and move the fragments to one location to increase efficiency.
**Disk partitions** can divide an individual drive into multiple logical drives, each with its own file system which can be mounted by the operating system and treated as an individual drive.
**Disk space analyzers** for the visualization of disk space usage by getting the size for each folder (including sub folders) & files in folder or drive. showing the distribution of the used space.
**Archive** utilities output a stream or a single file when provided with a directory or a set of files. Archive utilities, unlike archive suites, usually do not include compression or encryption capabilities. Some archive utilities may even have a separate un-archive utility for the reverse operation.
**File managers** provide a convenient method of performing routine data management tasks, such as deleting, renaming, cataloging, uncataloging, moving, copying, merging, generating and modifying data sets.
**Screensavers** were desired to prevent phosphor burn-in on CRT and plasma computer monitors by blanking the screen or filling it with moving images or patterns when the computer is not in use. Contemporary screensavers are used primarily for entertainment or security.
**System monitors** for monitoring resources and performance in a computer system.
**System profilers** provide detailed information about the software installed and hardware attached to the computer.
Application software
Application software is developed to perform in any task that benefits from computation. It is a set of programs that allows the computer to perform a specific data processing job for the user. It is a broad category, and encompasses software of many kinds, including the internet browser.
Types of Application Software:
Word Processing Software: Allows users to create, edit a document. Example: MS Word, Word Pad etc. Spreadsheet Software: performs calculations, analyze information, and visualize data in spreadsheet. Example: MS Excel, Lotus1-2-3 etc. Database Software: creates data bases and programs to track and manage information by using database software. Example: MS Access, MySQL, Oracle etc. Presentation Graphic Software: creates and edits presentations for slide shows, meetings and web pages. Examples MS Power Point Multimedia Software: Allows users to create image, audio, video etc. Example: Real Player, Media Player etc. Central processing unit
An Intel 80486DX2 CPU from above An Intel 80486DX2 from below The central processing unit (CPU) is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in use in the computer industry at least since the early 1960s.[1] The form, design and implementation of CPUs have changed dramatically since the earliest examples, but their fundamental operation remains much the same. On large machines, CPUs require one or more printed circuit boards. On personal computers and small workstations, the CPU is housed in a single silicon chip called a microprocessor. Since the 1970s the microprocessor class of CPUs has almost completely overtaken all other CPU implementations. Modern CPUs are large scale integrated circuits in packages typically less than four centimeters square, with hundreds of connecting pins. Two typical components of a CPU are the arithmetic logic unit (ALU), which performs arithmetic and logical operations, and the control unit (CU), which extracts instructions from memory and decodes and executes them, calling on the ALU when necessary.
Find all you need to know about the most common types of files on the internet. Our free Windows tutorials demystify zip, pdf and other types of files
Now that you are a little more confident using your PC, thanks to our Windows XP basics free Windows tutorials, free Windows Vista tutorials or our Windows 7 tutorials, it is time to move on to some more advanced topics. Don't worry though, nothing we cover in these free Windows tutorials is any more complicated than the videos you have already covered. Once you are familiar with the material presented here you will be able to use your PC and the internet much more effectively.
Common types of files in Windows and on the internet
When you are working and communicating with friends, family and colleagues you are likely to come across several types of file. Windows can handle many types of files without any additional software and almost all others with additional software. The table below shows you some of the most common types of file and what to do with them:- || File Type
Extension
What is it?
Need extra s/w to view?
Acrobat
.pdf
Text and/or picture document
Yes
Bitmap
.bmp
Picture
No
Document
.doc
Microsoft Word Document
No*
Excel sheet
.xls
Microsoft Excel Document
Yes
Executable
.exe
A computer program
No
GIF
.gif
Picture, often a graphic on a website
No
JPEG
.jpg
Picture, usually a photograph
No
PNG
.png
Picture, often a graphic on a website
No
Powerpoint
.pps
A Powerpoint presentation
Yes
Zip archive
.zip
A collection of compressed files
No
Microsoft word documents can usually be opened with Wordpad, the free word processor built into Windows. However certain Microsoft word documents which use advanced features may not open correctly with Wordpad.
As you can see, windows is well equipped to deal with most common types of files. These tutorials will focus on some of the more unusual types of files and how to work with them.
Pitfall - Hidden file extensions!
One of my least favourite features of Windows is its unhelpful "Hide file extensions" option. A file extension is the three or more letters following the dot on the end of a file name. For example, the file extension of "myfiles.zip" is ".zip". We covered the "hide file extension of known file types" option in other free Windows tutorials, specifically Windows XP basics tutorial 6 and Windows 7 basics tutorial 9. Windows Vista users may wish to watch this video too, since understanding the concept of "hidden file extensions" is important. Basically, Windows has the option of hiding the file extension part of a file name. For example, a zip file on your computer may be named "myfiles.zip". If you have the "Hide file extensions" option turned on, Windows explorer will show this file as "myfiles". We are not sure exactly why the designers of Windows made it this way, our best guess was it was an attempt to make things appear less complicated for beginners.
Above - Windows shows us a file called myfiles.zip, below - exactly the same file and folder but with the "hide file extensions of known file types" option turned on. These files are 100% identical, don't get caught out if you use this option!
Look at the picture below, with the "hide file extensions" option turned on, it looks as though we can have files with the same name in the same folder! Look closely though and you can see the icons are different. The actual names of these files are myfiles.zip, myfiles.txt and myfiles.bmp, but again Windows is hiding those file extensions from us!
Now you understand this somewhat confusing state of affairs, you have mastered one of the most common pitfalls when working with files in Windows. This one still catches us out from time to time, so beware!
What are Zip files?
When transporting a large number of files across the internet, by e-mail the web or any other means, it is not usually convenient to send them one by one. More experienced computer users usually prefer to use Zip files. A Zip file acts like a container, or perhaps a suitcase, letting you put lots of smaller files inside it. Furthermore, Zip files use a special software technique called "compression" which shrinks the size of the files you store to minimise the time it takes to transmit them across the internet. Unlike your holiday suitcase though, squashing more things inside a zip file won't ever cause damage to them.
Windows XP and Windows Vista can both open Zip files automatically, just double click on a Zip file to inspect its contents. You may have already been working with Zip files without even knowing it, since clicking on a Zip file simply displays its contents in a Windows Explorer window.
Wouldn't it be great to create our own Zip files, to send files and photographs to our friends across the internet? Windows Explorer comes with some basic support for creating Zip files, if you want to make your own Zip files in Explorer, take a look at this tutorial.
PDF files are used for a wide range of digitally stored documentation
Nothing to do with acrobatics, Adobe Acrobat/pdf files are very common on the internet and in business. In the days before fast, powerful multimedia computers were commonplace, chances are you would buy a computer program from a store and receive a printed instruction manual. Nowadays more and more companies are saving money by including manuals in pdf format. Pdf files are also used for forms and receipts and sometimes also letters and business correspondence. Unlike web pages or word processor documents, pdf files are designed to look identical on any machine that can open them and in the case of instruction manuals or other documents, identical to the paper hard-copy they are based on.
While Windows cannot open pdf files without extra software, the required software is free to download and easy to install. Visit this page to download Acrobat Reader and then install it to start viewing pdf documents on your PC.
COMPUTER SOFTWARE
Computer software, or just software, is a collection of computer programs and related data that provides the instruction code for telling a computer hardware what to do and how to do it.
Software refers to one or more computer programs and data held in the storage of the computer for some purposes. In other words, software is a set of programs, procedures, algorithms and its documentation concerned with the operation of a data processing system.
Program software performs the function of the program it implements, either by directly providing instructions to the computer hardware or by serving as input to another piece of software.
Types of software
Software can be divided into twoparts:System software
System software provides the basic functions for computer usage and helps run the computer hardware and system. System software is responsible for managing a variety of independent hardware components, so that they can work together harmoniously.It includes a combination of the following:
Operating system
An operating system (OS) is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system. A user cannot run an application program on the computer without an operating system, unless the application program is self booting.Types of Operating system
- Real-time: A real-time operating system is a multitasking operating system that aims at executing real-time applications. Real-time operating systems often use specialized scheduling algorithms so that they can achieve a deterministic nature of behavior. The main objective of real-time operating systems is their quick and predictable response to events. They have an event-driven or time-sharing design and often aspects of both. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.
- Multi-user: A multi-user operating system allows multiple users to access a computer system concurrently. Time-sharing system can be classified as multi-user systems as they enable a multiple user access to a computer through the sharing of time. Single-user operating systems, as opposed to a multi-user operating system, are usable by a single user at a time. Being able to use multiple accounts on a Windows operating system does not make it a multi-user system. Rather, only the network administrator is the real user. But for a Unix-like operating system, it is possible for two users to login at a time and this capability of the OS makes it a multi-user operating system.
- Multi-tasking vs. Single-tasking
When only a single program is allowed to run at a time, the system is grouped under a single-tasking system. However, when the operating system allows the execution of multiple tasks at one time, it is classified as a multi-tasking operating system. Multi-tasking can be of two types: pre-emptive or co-operative. In pre-emptive multitasking, the operating system slices the CPU time and dedicates one slot to each of the programs. Unix-like operating systems such as Solaris and Linux support pre-emptive multitasking, as does AmigaOS. Cooperative multitasking is achieved by relying on each process to give time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking. 32-bit versions, both Windows NT and Win9x, used pre-emptive multi-tasking. Mac OS prior to OS X used to support cooperative multitasking.Examples of operating system
Windows, MS DOS, Linus, Macintosh, etc.Windows operating system is the most common OS and there are various versions from Windows 95 to Windows 7.
A Translators
A Translator is a computer program that translates one programming language instruction(s) into another programming language instruction(s) without the loss of original meaning.Types of Translators
Compiler: If the translator translates a high level language into an assembly or machine language it is called a compiler. Examples include Ada, ALGOL, BASIC, COBOL, FORTRAN etcInterpreter: If the translator translates a high level language into an intermediate code which will be immediately executed it is called interpreter. Examples include APL, ASP, CYBOL, LISP, Smalltalk, PHP and PERL.
Decompiler: If the translator translates target/machine code to source language it is called a Decompiler. Example: DCC, Boomerang Decompilers and Reverse Engineering Compiler (REC).
Assembler: If the translator translates assembly language to machine code such kind of translator is called assembler. Examples include MASM, TASM, NASM and FASM.
Disassemble: If the translator translates machine code into assembly language such kind of translator is called Disassembler. Examples include gdb, IDA Pro and OllyDbg.
Utility software
Utility software is system software designed to help analyze, configure, optimize or maintain a computer. A single piece of utility software is usually called a utility or tool.Utility software usually focuses on how the computer infrastructure (including the computer hardware, operating system, application software and data storage) operates. Due to this focus, utilities are often rather technical and targeted at people with an advanced level of computer knowledge.
Utility software categories
Application software
Application software is developed to perform in any task that benefits from computation. It is a set of programs that allows the computer to perform a specific data processing job for the user. It is a broad category, and encompasses software of many kinds, including the internet browser.Types of Application Software:
Word Processing Software: Allows users to create, edit a document. Example: MS Word, Word Pad etc.Spreadsheet Software: performs calculations, analyze information, and visualize data in spreadsheet. Example: MS Excel, Lotus1-2-3 etc.
Database Software: creates data bases and programs to track and manage information by using database software. Example: MS Access, MySQL, Oracle etc.
Presentation Graphic Software: creates and edits presentations for slide shows, meetings and web pages. Examples MS Power Point
Multimedia Software: Allows users to create image, audio, video etc. Example: Real Player, Media Player etc.
Central processing unit
An Intel 80486DX2 CPU from above
An Intel 80486DX2 from below
The central processing unit (CPU) is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in use in the computer industry at least since the early 1960s.[1] The form, design and implementation of CPUs have changed dramatically since the earliest examples, but their fundamental operation remains much the same.
On large machines, CPUs require one or more printed circuit boards. On personal computers and small workstations, the CPU is housed in a single silicon chip called a microprocessor. Since the 1970s the microprocessor class of CPUs has almost completely overtaken all other CPU implementations. Modern CPUs are large scale integrated circuits in packages typically less than four centimeters square, with hundreds of connecting pins.
Two typical components of a CPU are the arithmetic logic unit (ALU), which performs arithmetic and logical operations, and the control unit (CU), which extracts instructions from memory and decodes and executes them, calling on the ALU when necessary.
Find all you need to know about the most common types of files on the internet. Our free Windows tutorials demystify zip, pdf and other types of files
Quick links:-Common types of files in WindowsPitfall - Hidden file extensions!What are Zip files? / 7Zip tutorialsWhat are pdf/Acrobat files?Comment on this article
Now that you are a little more confident using your PC, thanks to our Windows XP basics free Windows tutorials, free Windows Vista tutorials or our Windows 7 tutorials, it is time to move on to some more advanced topics. Don't worry though, nothing we cover in these free Windows tutorials is any more complicated than the videos you have already covered. Once you are familiar with the material presented here you will be able to use your PC and the internet much more effectively.
Common types of files in Windows and on the internet
When you are working and communicating with friends, family and colleagues you are likely to come across several types of file. Windows can handle many types of files without any additional software and almost all others with additional software. The table below shows you some of the most common types of file and what to do with them:-
|| File Type
As you can see, windows is well equipped to deal with most common types of files. These tutorials will focus on some of the more unusual types of files and how to work with them.
Pitfall - Hidden file extensions!
One of my least favourite features of Windows is its unhelpful "Hide file extensions" option. A file extension is the three or more letters following the dot on the end of a file name. For example, the file extension of "myfiles.zip" is ".zip". We covered the "hide file extension of known file types" option in other free Windows tutorials, specifically Windows XP basics tutorial 6 and Windows 7 basics tutorial 9. Windows Vista users may wish to watch this video too, since understanding the concept of "hidden file extensions" is important. Basically, Windows has the option of hiding the file extension part of a file name. For example, a zip file on your computer may be named "myfiles.zip". If you have the "Hide file extensions" option turned on, Windows explorer will show this file as "myfiles". We are not sure exactly why the designers of Windows made it this way, our best guess was it was an attempt to make things appear less complicated for beginners.
Above - Windows shows us a file called myfiles.zip, below - exactly the same file and folder but with the "hide file extensions of known file types" option turned on. These files are 100% identical, don't get caught out if you use this option!
Look at the picture below, with the "hide file extensions" option turned on, it looks as though we can have files with the same name in the same folder! Look closely though and you can see the icons are different. The actual names of these files are myfiles.zip, myfiles.txt and myfiles.bmp, but again Windows is hiding those file extensions from us!
Now you understand this somewhat confusing state of affairs, you have mastered one of the most common pitfalls when working with files in Windows. This one still catches us out from time to time, so beware!
What are Zip files?
When transporting a large number of files across the internet, by e-mail the web or any other means, it is not usually convenient to send them one by one. More experienced computer users usually prefer to use Zip files. A Zip file acts like a container, or perhaps a suitcase, letting you put lots of smaller files inside it. Furthermore, Zip files use a special software technique called "compression" which shrinks the size of the files you store to minimise the time it takes to transmit them across the internet. Unlike your holiday suitcase though, squashing more things inside a zip file won't ever cause damage to them.
Windows XP and Windows Vista can both open Zip files automatically, just double click on a Zip file to inspect its contents. You may have already been working with Zip files without even knowing it, since clicking on a Zip file simply displays its contents in a Windows Explorer window.
Wouldn't it be great to create our own Zip files, to send files and photographs to our friends across the internet? Windows Explorer comes with some basic support for creating Zip files, if you want to make your own Zip files in Explorer, take a look at this tutorial.
Want a more powerful Zip utility with better compression and support for other archive formats? Then you need the superb free 7-Zip package. Check out our free Windows tutorials on 7-Zip:-7-Zip tutorial 1 - Installing 7-Zip7-Zip tutorial 2 - Extracting files7-Zip tutorial 3 - Making your own zip files
PC acrobatics?! - What are pdf/Acrobat files?
PDF files are used for a wide range of digitally stored documentation
Nothing to do with acrobatics, Adobe Acrobat/pdf files are very common on the internet and in business. In the days before fast, powerful multimedia computers were commonplace, chances are you would buy a computer program from a store and receive a printed instruction manual. Nowadays more and more companies are saving money by including manuals in pdf format. Pdf files are also used for forms and receipts and sometimes also letters and business correspondence. Unlike web pages or word processor documents, pdf files are designed to look identical on any machine that can open them and in the case of instruction manuals or other documents, identical to the paper hard-copy they are based on.
While Windows cannot open pdf files without extra software, the required software is free to download and easy to install. Visit this page to download Acrobat Reader and then install it to start viewing pdf documents on your PC.